Improvement in automatic signal-boxes for fire-alarm telegraphs



M. G. CRANE & E. ROGERS. I

Automatic 8 ignal Box for Fire Alarm Telegfaphs.

Patented July 6, 1869.

me name pzvzns cm, morwwmm, mama-mu, n. c.

UNITE STATES PATENT OFFEQE MOSES G. CRANE, OF NEWTON, AND EDlVIN ROGERS,OF BOSTON, MASSA- CHUSETTS.

IMPROVEMENT IN AUTOMATIC SIGNAL-BOXES FOR FIRE-ALARM TELEGRAPHS.

Specification forming part of Letters Patent No. 92,275, dated July6,1869.

To all whom it may concern:

Be it known that we, Mo'sEs Gr; CRANE, of Newton, Middlesex county, andEDWIN ROG- ERS, of Boston, Suffolk county, all in the State ofMassachusetts, have invented an Improvement in Automatic Signal-Boxesfor FireAlarm Telegraphs; and we do hereby declare that the following,taken in connection with the drawings which accompany and form part ofthis specification, is a description of our invention suflicient toenable those skilled in the art to practice it.

The invention relates to the construction and organization of themechanism of signalboxes for fire-alarm telegraphs, with reference tothe means employed for automatically actuating a circuit-wheel by theinfluence of a weight exerted through a train of gear mechanismconnecting the weight with the circuitwheel, this weight, in normalposition, exerting no stress upon the gearing, but being so disposedthat it can be raised by a lever having a finger-piece extending throughthe door of the box, the person who wishes to give the signal simplythrowing the finger-piece down,

' and thereby raising and setting the weight so that it will actuate thecircuit-wheel by itsgravity.

Premising, for the purpose of this specification, the combination,broadly, of the weighted or spring lever, a train of gearing, and=acircult-wheel, (the latter operated by the weight or spring through thetrain of gearing,) to be old, orv at least not a part of the presentimprovements, this invention may be stated to consist of thefollowingdetails of construction and arrangement: The combination of theweighted lever with the gear-train by means of a reciprocatinggearsector or setting-gear, whose teeth mesh into a pinion turningloosely on its shaft in one direction, and being fast upon and drivingsaid shaft when rotating in the opposite direction; the combination,with the escapement-wheel of the gear-train,- of a pallet, having areciprocating fly, for regulatin g the motion of the circuit-wheel. Thecombination, with the lever-weight and gear-train, of springs, sointerposed between the weight and the first or main gear as to preventsudden or concnssive strain upon the gear-teeth when the weight beginsto fall; the combination,- with the weighted lover, of means forpreventing it from being operated or lifted when the circuit-fingers ofthe circuitwheel are passing over-the breaks thereof, and for allowingit to be lifted when the fingers are passing over the blank or unbrokenportion of the perimeter of theeircuit-wheel.

The drawing represents a signal-box and mechanism embodying theseimprovements.

A shows the mechanism in front elevation, the lever by which the weightis raised, and

which is hung uponthe door of the box,

being represented in red lines. B shows the mechanism in plan. 0 is asection on the line 0. denotes the box which contains and incloses themechanism. 1) I) represent the arbor or pillar-plates of the gear-train,the main shaft 0 of which train carries the circuit-wheel d, rotation ofwhich makes and breaks the circuit formed by the wheel and themain-circuit wires. The shaft 0 also carries a gearwheel, a, fixed uponit, anda loose pinion, f, said pinion turning loosely in one direction,but being locked to and moving the wheel a when turning in the otherdirection, by means of a catch or pawl-wheel, g, fixed to the pinion,and a click or spring-pawl, h, fixed to the wheel,the click slippingover the pawl-wheel one way, or when the wheel rotates in one 7direction, and slipping down in front of the teeth when the wheelrotates in the opposite direction.

Engaging with the pinion is a gear-sector, vi, hung, by means of an arm,A, to a shaft, I, to which shaft the arm is fixed, said shaft alsocarrying at its outer-end a lever-arm, m, to the outer end of which ishung theweight n, the sector-arm k and weighted arm m forming together alever, of which the shaft 1 is the fulcrum, which lever' is acted uponby the powerfurnished by the weight n, and acts upon. the pinion fthrough the sector-teeth, and through it turns the gear-wheel c andcircuit-wheel d. p

Upward movement of the levcr-armm throws the sector-gear down, (thepinion f turning lo0sely,) and whenthe lever-arm, after being raised, isreleased, the weight upon the arm automatically imparts such rotation,through the sector-gear, to the gear-shaft and circuit wheel.

To retain the sector-teeth in engagement with the pinion, and to limitthe number of rotations of the circuit-wheel, the extent of movement ofthe sector-arm is limited, the arm Zc strikingagainst a pillar, 0, whenthe weight is raised to set the train, and against another pillar, p,when the weight runs down, the weight, when released after being raised,always actuating the train and rotating the circuit-wheel until thesector-arm strikes the post p.

As the weight is thus brought to a sudden stop, it is liable, throughits momentum, to injure the teeth in the train, unless some provision ismade to lessen the shock. To accomplish this, one or more springs areinterposed between the weight and the pawl-wheel h.

a In the drawings two such springs are shown, the weight a beingdirectly hung to a spring, g, and the click I being formed upon the endof a spring, r, each spring yielding to the momentum of the weight whenthe sector-lever stops, such momentum being'thus spent upon the springsinstead of upon the gears of the train. One or more springs may bedifferently disposed for this purpose, though the arrange ment shown issimple and effective.

The circuit-wheel dis metal-surfaced, and

- the metal is broken by insulated spaces corresponding to the stationof the signal-box.

The wheel shown in the drawings designates station 32, there being threeinsulated pieces or breaks in the metal perimeter of the wheel, denotingthe number 3, separated by short spaces of metal from each other, and bya. longer space of metal from two similar spaces or breaks, the rest ofthe surface of the wheel being occupied by a long space of metal. On thesurface of the wheel rests a series of springfingers, 8, one or more foreach wire t of' the main circuit, one of which fingers rests upon thesurface of the wheel having in line with the insulated spaces or breaks,so that such breaks pass under the finger as the wheel re-' volves.

When the .fingers are both in contact with the connected metal of thewheel, the circuit is closed, and as the wheel rotates, the circuit isbroken as often as one of the breaks or insulated spaces comes under theouter finger,

the number of short interruptions between the insulated spots denotingthe first number of the station, the'longer space between the first andsecond series of insulations making the interruption between thesignals, to enable the numbers to be distinguished, and the contact a ofthe outer finger with the insulated pieces of the second seriesdetermining the second number of the station from whence the signal issent the contactof the fingeriwith the long blank space of thewheel-perimeter making the long interval between the successive signalsgiven from the box.

To regulate the velocity of the circuit-wheel, or to render the movementuniform and regular, an escapement-shaft, a, is geared to thecircuit-wheel shaft by a pinion, c, said shaft a bearing ancscape1nent-'wheel,w, with the:

teeth of which the teeth of a pallet, :10, engage, said pallet beingfixed upon a rocker-shaft, g, which has projecting from it the twoblades of a reciprocating or vibrating fiy, z. The weighted. lever israised from the outside of the box by means of a lever, a the mechanismthrough which this is effected being as follows: The lever at hasprojecting from it a pin, b and when the weight has de- The lever a isheld in normal position by a spring, h, in which position the lifter cis at its lowest point. If the finger-piece e is now depressed, thelifter 0 will raise the lever, and thus set the weight so that it willact upon the train of gears and rotate the circuit-wheel, as beforedescribed, the lever a. being returned to normal position by the springW, as seen, as the projection a is released from the fingers.

To prevent obstruction of the movement of the lever m while theirisulations or breaks of the circuit-wheel are under thefingers s,which obstruction would cause a false signal to be given by falseinterruptions, and which false interruptions might be caused by liftingthe weight while the fingers s and breaks were passing in contact, thepin b is so arranged that itcan only be operated by'the lever a when theweight has rundown, or during the long pause after each complete signal.For this purpose a plate, 1", is fastenedupon the inner or train box i,this plate having a series of inclines, m lying in the path of movementof the pin 1). The pin 1) plays loosely through the lover a, and isfastened to a spring, a",

which presses it back toward the platez".

When the weight is down, the inner end of the pin (which is madeconical'or with a conical head) rests against the apex of one of theinclines m, in which position the outer end of the pin projects out intothe path of the lifter c. When the weight is raised the circuitwheel isin position to commence to signal as soon as the weight is released andbegins to fall, the lifter being returned to normal position by thespring h, the lifter swinging upon a pin, 0, and being pressed out by aspring, 1;, which spring allows the lifter to fall back, as, indescending, it passes in contact with the pm I), as will be readilyunderstood. In this position the pin is borne inward by its spring andrests against the plate 6 and cannot be touched by the lifter. Thebreaks or insulations in the circuit-wheel, having passedthe fingers s,the pin is brought against the upper incline m, and is pressed outthereby; and while the wheel is rotating, until the breaks again reachthe fingers, the weight may be raised by the lifter, the pin slidingback. out of the path of the lifter, when the breaks again approach thesprings, and so on, until the weight has fully descended, thus allowingthe weight to be fully reset at any time while the signal is not beingtransmitted, and preventin g any interruption in the descent of theweight while the signal is being immediately transmitted.

What is claimed is-- 1. The combination, with an automatic sig- 3. Incombination with the gear-train, and an escapement. and pallet connectedthereto, a reciprocating fly placed directly on the palletshaft,substantially as described.

4. In combination with the setting-lever a,

and the slot through which the fin ger-piece of the lever traverses, thestationary guard-plate g, substantially as described.

5. In'combination with the lever a the swin ging or spring-lifters,substantially as shown and described. x v

6. In combination with the weighted lever, the slide-pin b ,'so arrangedthat while it may be actuated by the lifter whenever the signal isnot-being transmitted, it cannot be operated while the signal is incourse of transmission.

MOSES G. oRAnn. EDWIN noenns.

Witnesses:

FRANCIS GoULn, J. B. ORosBY.

